We report new measurements of the decays $Btorho^+ gamma$, $B to rho^0 gamma$ and $B to omegagamma$ using a data sample of $657 times 10^6$ $B$ meson pairs accumulated with the Belle detector at the KEKB $e^+ e^-$ collider. We measure branching fractions ${cal B}(B^+ to rho^+ gamma) = (8.7^{+2.9}_{-2.7}{}^{+0.9}_{-1.1})times 10^{-7}$, ${cal B}(B^0 to rho^0 gamma) = (7.8^{+1.7}_{-1.6}{}^{+0.9}_{-1.0}) times 10^{-7}$ and ${cal B}(B^0 to omega gamma) = (4.0^{+1.9}_{-1.7} pm 1.3) times 10^{-7}$. We also report the isospin asymmetry $Delta (rhogamma) = -0.48^{+0.21}_{-0.19}{}^{+0.08}_{-0.09}$; and the first measurement of the direct CP-violating asymmetry $A_{CP}(B^+ to rho^+ gamma) = -0.11pm{0.32}pm{0.09}$, where the first and second errors are statistical and systematic, respectively.
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